Fill a pot with water, and add chicken. Bring to a boil, reduce and simmer until completely cooked. When chicken is cooked, slice and spread mustard over the chicken, toss to coat, add about ΒΌ cup water.
Mix the chicken, cheese, cilantro, spices and the diced avocados.
Spread 1 tablespoon sour cream on each tortilla, add 1/8th of the mixture, form a roll. Finish all burritos.
Heat 1 tablespoon oil into a pan and place all four tortillas on the pan, cook for 2 minutes on medium- high heat. Flip on the other side and cook for another minutes or until the the tortillas are golden
Serve warm.